@ Heat Treatment: Annealing To adjust Micro Structure and Hardness. Purpose: To improve machining property and avoid potential possible distortion when use in future.
@ Shape Rectification Applicable, by "Oil Pressure Machine". Notice Over Pressure issue when rectifying.
*** NOTES (why shape/dimension Rectification is necessary for some castings)
Not like machined parts, investment castings will deform in varying degree during production. Usually, it is the biggest problem for this kinds of parts. Reasons as below:-
1/ Wax mold deformation (one main reason; wax is SOFT) 2/ When casting process, during cooling down, SHRINKAGE will lead to deformation in different position/direction especially for those Asymmetrical part. (another main reason) 3/ Shot Blasting also will lead deformation a little bit. 4/ If Heat Treatment is needed, Deformation also might happen after this process.
In order to obtain correct dimensions, especially for those with critical tolerance requiriement, Rectification is necessary. Usually, for small parts, the deformation is not obvious, rectification will be not needed.
Optional Final Finish/Surface Treatment for Castings Including:-